"There, I said it. Microsoft has been bombarding the media with claims about how much better IE9 is than all the other browsers, more HTML5 and CSS3 compliant than any other browser that ever existing and ever will. It's the only browser that passes all the tests they made up. And, Microsoft has finally implemented the CSS3 selectors that were implemented by other browsers back in, what? 2003? Because Microsoft has updated IE to support CSS3 selectors and rounded corners, they want us to believe that somehow IE9 magically supports the whole slew of CSS3 visual styling. I'm afraid it doesn't. As a matter of fact, IE9's support for CSS3 visual styling is so poor that the results are shocking."

Sorry, Thom, but I think you did a mistake posting some FUD about Microsoft made up by some moron who knows exactly what he is doing.

That moron has made on pourpose a page which can only work with Webkit specific experimental features no other browser engine shoud use. And then went bashing Microsoft for being incapable of doing something they must not do.

In fact, the rendering of that page works is very similar in his IE9 and in my Opera 10.63, but Opera doesn't do rounded corners or the shadows. Firefox doesn't do the shadows, so I assume he has used some Webkit-only thing.

Looking the code, the reason for the lack of rounded corners is pretty obvious: it uses -webkit and -moz properties for rounded corners, which should only work on Webkit (Chrome, Safari...) and Gecko (Firefox...). Opera follows the standards to the letter here, and only supports rounded corners without those prefixes.
So what's shocking me now is the fact that IE9 is painting round corners, because, following the standards, it shouldn't.

Every modern browser has mistakes in standards support; they are very well known by web developers, so making a test to make any of them look bad is usually a matter of knowing how to use Google.

The promise of "Same Markup" is a noble goal, but no browser has ever been able to attain it. Some of the reasons are technical (it is a very, very difficult thing to do), but I think that nowadays no browser vendor can achieve a complete standards support because of two reasons:
- Standards are not as precise as they should. There are some obscure issues not covered by them; it is usually solved by agreements between browsers to do it the same way, or by copying the first one who implemented it.
- Standards are a work in progress. CSS 3 is only a draft! HTML 5 is being written! They aren't even standards; they will be standards once they have been completed and approved, but they aren't now, it may requiere years to get there! W3C could decide to kill them, or make radical changes, and what then? We would have a world wide web full of non-standard pages running in non-standard browsers. They would not do as much (they would get the worse of it), but it should be expected little changes, which are going to break current browsers and pages. Anyway, by definition, if a standard is not finished, you can't say you are following it.

This is a publicity stunt by a moron with a blog nobody reads, and you are giving him a lot of visits and misleading your readers. Please, Thom, remove the link, or make an update with a correction. I love your work to much to see it ripped by this mistake.